Once Sara encounters the Indian Gentleman in person, everyone’s truth starts coming out fairly quickly, only drawn out by Carrisford’s stumbling reluctance to ask directly, lest he be disappointed once again. Sara refers to Ram Dass as a Lascar, leading to the revelation that she was born in India. Now, this on its own means little--no doubt all sorts of Anglo-Indian girls were sent to school in London. As Sara’s position at the school is teased out, Carrisford becomes more and more agitated and hands the questioning over to Carmichael. But Carmichael, too, seems strangely reluctant to simply ask her name outright. So we’re led through the circumstances of Captain Crewe’s ruin and death and Sara--not suspecting anything--lays the blame squarely on her father’s friend. This knife-twist releases the last of the debt between them. Now Carmichael asks her name and all is revealed.
Sara is stunned and bewildered to think that her salvation had been right next door all this time. (We’ll continue right on in to Chapter 18 now, since it’s all part of the same scene.) When Sara is sent out of the room to join the Carmichael children while Carrisford recovers, Donald is the one who point out this irony: “If I’d just asked what your name was when I gave you my sixpence, you would have told me it was Sara Crewe, and then you would have been found in a minute.” But like Dorothy and the ruby slippers, if the connection had been made at the beginning, there would have been no opportunity for all the spiritual growth along the way. And it is Carrisford's (in his mind) displaced charity toward "the little girl who is not a beggar" that creates his own redemption--a redemption that wouldn't have occurred if he had simply tracked Sara down at the beginning of his search. (Though--standing outside the narrative framework of Moral Accounting--it's a bit abhorrent to think that two years of suffering on both their parts is a fair trade for a neat redemptive arc.)
Mrs. Carmichael comes over to take charge of Sara and mother her (which must have felt peculiar to Sara, given that she had never been mothered in her life). And she is the one who makes the other connection for Sara: that Mr. Carrisford is Sara’s benevolent friend who transformed her attic. This allows Sara to forgive him everything else and they can begin their new relationship as guardian and ward with a relatively clean slate. All that remains, is for accounts to be settled with Miss Minchin and the school...
As I’ve indicated above, I think that from the Moral Accounting point of view, this scene completes both Sara and Carrisford’s moral arcs. Sara is rewarded for her virtue, and Carrisford has atoned for his sin. What they do moving forward is written in a new account book.